Fastening device for bands, straps and the like



Oct l. 1957 J. RAVE 2,807,852

FASTENING DEVICE FOR BANDS, STRAPS AND THE LIKE 2 Sheets-Sheet 1 Filed Sept. 2, 1955 myn/ron c/azz a Fe Oct l 1957 J. RAVE 2,807,852

FASTENING DEVICE FOR BANDS, STRAPS AND THE LIKE Filed Sept. 2, 1953 2 SheetsSheet 2 /IV VE IV T 0l? Jean Fa Ife TTR EY FASTENING DEVICE FCR BANDS, STRAPS AND` THE LIKE Jean Rave, Nice, France Application September 2, 1953, Serial No. 377,997

Claims priority, application Germany February 3, 1953V 9 Claims. (Cl. 24-197) The present invention relates to fastening devices for flexible bands, straps, belts and the like.

This fastening device includes a slide provided with two slots and which can be'slipped along the strap. The two slots of the slide are separated from each other by a cross piece around which is looped one of the ends of the strap whlch, in the operative position of the fastening device, 1s caught between this cross piece of the slide and the front cross bar of a loop which constitutes the other element of the fastening device.

This loop includes, between its front and rear cross bars, an opening having two portions of different widths, the portion of greater width being located at the rear of the other one and being of a width sufcient to enable the slide to pass therein for assembly and release of the fastening device, whereas the sides of the loop, which constitute the side edges of the other portion of said opening, which is of smaller width, form a support for the slide when said slide and said loop are assembled together.

The chief object of my invention is to provide a fastening device of this kind which is perfectly safe and cannot open accidentally by the mere effect of a loosening of the strap, while making it possible to release the fastening device instantaneously at any time and whatever be the pull exerted by the strap.

According to my invention, the length in the longitudinal direction of the rear portion of the loop opening is smaller than the distance from the rear edge of the slide to the rear edge of the cross piece of said fslide and the length in the longitudinal direction of the front portion of said loop opening is smaller than the sum of the thickness of said strap and of the distance from the rear edge olf said slide to the front edge of the cross piece of said s ide.

Preferred embodiments of my invention will be hereinafter described with reference to the accompanying drawings, given merely by way of example, and in which:

Fig. 1 separately shows the loop and the slide of the' fastening device according to my invention.

Fig. 2 shows the assembly of these two elements mounted at the ends of a strap. Y

Fig. 3 is a cross section on the line III- III of Fig. 2.

Fig. 4 shows the assembly of Fig. 2 justv when the loop andthe slide are going to be separated from each other.

Figs. 5 and 6 are views analogous to Figs. 1 and 4 respectively, relating to a modication.

The fastening device according to my invention includes two elements 1 and Z adapted to be hooked to each other so as to assemble together the respective ends of a exible strap 3, the above mentioned elements 1 and 2 being respectively fixed to the ends of said strap. f

Element 1 constitutes a slide the position of which on strap 3 is adjustable at will. It is provided for this purpose with two slots 4 and S, separated from veach other by an intermediate cross piece 6.

For the sake of clarity, it will be supposed in what follows that the expressions front and rear which are to be used hereinafter are such that the front correited States Patent rrce sponds to the right hand side of the drawing and the rear to the left hand side thereof.

The end 3a of strap 3 is looped around the intermedi- `ate cross piece 6 of the slide, said looped end of strap 3 passing inside the slots 4 and 5 of said slide. To be more complete, strap 3 passes from under slide 1 through the slot 4 thereof, then around cross piece 6 and back through slot 5, so as to end at 3a after having formed a kind of loop around said cross piece 6.

Element 2 constitutes the loop, which is iixed to the other end 3b of strap 3. This loop 'includes a front cross bar 2a and `a rear cross bar 2b and it forms between these two cross bars 2a, 2b, an opening including two portions of different widths. The portion of greater width is located at the rear and this width is sufficient to atord passage to slide 1 for assembly and release of the fastening device. The longitudinal sides 2c and 2d of loop 2, which form the sides of the other portion of said opening (which is of smaller width than the outer width of the slide) form a support for said slide when the slide has been engaged over the loop in the position of assembly illustrated by Figs. V2 and 3. In this position, the end 3a of strap 3 is caught between the intermediate cross piece 6 of the slide and the front cross bar 2a of the loop and it is held in position by the pull exerted by strap 3 in the direction of the arrow on slide 1.

My fastening device in this assembled position must comply with the two following conditions:

I. The intermediate cross piece 6 of slide 1 which is bearing through its extremities 1c and 1d upon the sides 2c and 2d of the narrow portion of the opening of loop 2 must not, as a consequence of any translatory movement due to a loosening of the strap, come into a position where the slide would pass through the widest portion of the opening of the loop;

II. At least as long as it is subjected to a pull in the direction of the arrow (Fig. 2), slide 1 must have its rear edge 1b located above the wider portion of the opening of the loop. y

In order to comply with these conditions, according to my invention, I choose the respective lengths A and B, in the direction of the axis of strap 3, of the two portions of the opening of the loop, and also the respective distances C and D between, on the one hand, the front edge of the intermediate cross piece 6 of the slide 1 and the rear edge 1b thereof, and on the other hand, the rear edge of said intermediate cross piece 6 and the rear edge 1b of said side 1, as a function of the thickness F of strap 3, such that when slide 1 is, as shown by Figs. 2 and 3, in assembed position, the distance E between the rear edge of the slide and the rear limit 7 of the wider portion ofthe opening of the loop, is smaller than both the length A of this portion of said opening and the distance G between the rear limit S of the narrow portion of the loop and the It will be readily understood that a fastening device which complies with these conditions cannot open accidentally due to the mere effect of a loosening of strap 3, which would enable the slide to slip along the loop in a direction opposed to that of the arrow of Fig. 2, When the above conditions are complied with, slide 1, when it is moving along loopY 2 toward the left, bears through its rear edge 1b against said loop before the rear edge of the intermediate cross piece 6 of said slide comes opposite the wider portion of the opening in loop 2. Consequently, even if this movement took an amplitude such that cross piece 6 came opposite the wider portion of the opening of loop 2, the device could not be released, that 3 is to say slide 1 could not swing through the wider portion of the opening of loop 2.

On the other hand, a fastening device corresponding to the second of the above mentioned conditions makes it possible instantaneously to separate elements 1 and 2 at any time even when strap 3.,is pulling them relatively to each otherin the direction of the arrow, as shown'by Fig. 2. 'Itrsucem to obtain this result, to rotate slide' 1 as shown by Figs. 4 and 6 by pulling its front edge 9 so as to Ypivot it into the wider zone of the opening of the loop about edges 8 which form the front limit of said portion.

If F is the thickness of strap 3, Fig. `3 shows that:

Fig. 3 also shows that:

G=VBF -the vdistance between the edges `of cross piece6 Fig. l shows that the distance between'the edges of cross piece 6 is equal to C-D.

Therefore:

G :B -F- C -D =B+D C+F The ,above mentioned first condition:

( l VE G The above mentioned second condition:

corresponds to:

A+B-(C-l-F) A that is to say:

Therefore, according to my invention, the length A in the longitudinal direction of the rear portion (of a width greater than the outer width of slide 1) of the opening of loop 2 is smaller than the distance D `from the rear edge of slide 1 tothe front edge of the cross piece 6 of said slide, and the length B in the longitudinal direction of the front portion (of a width smaller Vthan the outer width of slide 1) is smaller than 'the sum of the thickness F of the strap and of the distance C from the rear edge of slide 1 to the front edge of the cross piece 6 of said slide.

ln order to be able to reduce to a minimum the length A of the wider portion of the opening of loop 2, without preventing the passage of slide 1 which .carries strap 3 looped about its intermediate cross piece 6, from passing,

as shown by Fig. 4 through said wider portion of the opening in loop 2, the rear cross bar 2b of the loop is preferably provided with a notch 10 the widtlrand depth of which correspond to those of strap 3.

In order to give strap 3 the desired tension when the elements of the fastening device are in the position indicated by Figs. 2 and 3, it suces to pull the end 3a of said strap.

In the embodiment illustrated by Figs. 1 to 4, the two elements 1 and 2 of the fastening device may be obtained by stamping from a metal sheet. When the fastening device is to be mounted on a belt, the elements can then be slightly bent to accommodate strap 3, the lug 9 being curved in the opposed direction so as to permit ofeasily releasing the fastening device.

In the embodiment illustrated by Figs. and 6, the sides 2c and `2d which form with the `,front cross bar l2a offloop 2 a supportA for slide 1 carry, integral therewith, twoV ribs 2e and 2f parallel to each-other and projecting from the plane of said support, these two ribs being joined behind the wider portion of the opening by a cross rib 2g which constitutes an abutment for the slide when said slide is moving toward the left with respect to the loop.

Advantageously, as shown by Figs. 5 and 6, the sides 1e and 1f of the slide project with respect to the intermediate cross piece 6 to a distance at least equal to the thickness of strap 3. Thus, the loop formed by strap3 around said intermediate cross piece does not project from said cross piece.

Preferably, the loop and the slide of the fastening device shown by Figs. 5 and 6 are made of a moldable plastic material, such as that known under the name of nylon `I thus obtain a device which does not oxidize and is refractory to any corrosion by atmospheric agents. Advantageously, the projecting sides 1e and 1f are joined together on the front cross bar of the slide immediately behind lug 9.

The slide is thus reinforced 'by aprojecting edge forming a kind of U which makes it very strong and corresponds to the structure of the loop including ribs 2e, 2f, 2g, alsoin the form of a U or a H,as shown by the drawing.

As the self-tightening `properties of fastening devices according to my invention are very eicient, it is advantageous to round off the edges which. are in contact with strap 3, and in particular those of the intermediate cross piece 6 of the slide and of the rear edge of the front cross bar 2a of the loop, inorder to avoid deteriorating strap 3.

Furthermore, it is advantageous to give rounded shapes to the angles of the two pieces, and especially to those of the slide, as shown by the drawing, which further facilitates the operation of the fastening device.

Thefastening device according to my invention is applicable to all kinds of straps, bands or even elements of rounded cross section, especially if the openings 4 and 5 and the rearedge of the cross bar 2a of the loop are given a suitable shape for this purpose.

Ina general manner, while'l have, in the above description, disclosed what I deem lto be practical and efficient embodiments of my invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the ,present invention, as comprehended within the scope of the accompanying claims.

4What I claim is:

1. A fastening device comprising a rigid loop having a rear cross bar and a front cross bar longitudinally opposed thereto, ka exible strap, band or the like secured at one of its extremities to said rear cross bar, and a rigid slide` comprising a frame having a pair of parallel slots with a cross piece therebetween looped by the opposite` free extremity of said strap `passing through said parallel slots, said loop forming between its front and rear cross bars an opening .including two portions of different respective widths .located one behind the other in the longitudinal direction, the inside width of the portion of said `opening -Which is at the rear of the other portion being wider thanthe `outer width of said slide to permit free passage of said slide therethrough, the front portion of said opening having a pair of parallel longitudinally extending sides so positioned that the inside width of saidfront portion .of ,said opening is smaller than Vthe `outer width of said slide to cooperate therewith to support it when said strap is tensioned, the length in the longitudinal direction of said rear portion of said opening being smaller thanthe distance from the rear edge Yof said slide to .the .rear `edge of said cross piece of said slide andthe length in the longitudinal direction of said front `portion of saidopening being smaller than the sumv of the thickness of said strap and-of the distance from the rear edge of said slide to the front edge of said cross piece of `.said slide.

2. A fastening device according to claim l in which the loop is provided at the rear of the Wider portion of the opening thereof with a notch of a width smaller than the outer Width of the slide but suiciently wide to accommodate the strap.

3. A fastening device according to claim l further including on the loop a projecting abutment rearward of the opening thereof.

4. A fastening device according to claim l further including guides for the slide carried along the side edges of the opening of said loop and projecting on either side of said slide.

5. A fastening device according to claim l in which the sides of the slide project with respect to its intermediate cross piece to a distance corresponding to the thickness of the strap.

6. A fastening device according to claim l further including guides for the slide carried along the side edges of the opening of said loop and projecting on either side of said slide, said guides forming ribs connected together at the rear of the opening of said loop.

7. A fastening device according to claim l in which the sides of the slide project with respect to its intermediate cross piece to a distance corresponding to the thickness of the strap, said projecting sides being connected together at the front of the slide.

8. A fastening device according to claim l in Which the edges of the slide and of the loop which cooperate with said strap having rounded angles.

9. A fastening device comprising a rigid loop having a rear cross bar and a front cross bar longitudinally opposed thereto, a flexible strap, band or the like secured at one of its extremities to said rear cross bar, and a rigid slide comprising a frame having a pair of parallel slots with a cross piece therebetween looped by the opposite free extremity of said strap passing through said parallel slots, said loop forming between its front and rear cross bars an opening including two portions of dilerent respective widths located one behind the other in the longitudinal direction, the inside Width of the portion of said opening which is at the rear of the other portion being Wider than the outer Width of said slide to permit free passage of said slide therethrough, the front portion of said opening having a pair of parallel longitudinally extending sides so positioned that the inside width of said front portion of said opening is smaller than the outer width of said slide to cooperate therewith to support it when said strap is tensioned, the length in the longitudinal direction of said rear portion of said opening being smaller than the distance from the rear edge of said slide to the rear edge of said cross piece of said slide, the length in the longitudinal direction of said front portion of said opening being smaller than the sum of the thickness of said strap and of the distance from the rear edge of said slide to the front edge of said cross piece of said slide, and the distance in longitudinal direction between the loop rear cross bar and the loop front cross bar being greater than Vthe sum of the thickness of said strap and of the distance from the rear edge of said slide to the front edge of said cross piece of said slide.

References Cited in the lile of this patent UNITED STATES PATENTS 

